• Title/Summary/Keyword: access

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A study on the transformation of the fisheries relations in accordance with the changes in Japan and Russia Fisheries Agreement (일본과 러시아 간 어업질서의 재편에 따른 양국 어업관계의 변모)

  • Kim, Dae-Young
    • The Journal of Fisheries Business Administration
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    • v.46 no.2
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    • pp.93-110
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    • 2015
  • This research examined the transformations of the fisheries relations between Japan and Russia since the establishment of the Exclusive Economic Zone (EEZ) system. The author reviewed the transformations with investigation on mutual fishing access to EEZ including salmon & trout catches. The Japan-Russia fisheries relations have evolved through multiple developmental stages, which include mutual fishing access to EEZ, the reductions of a fishing quota to balance catches of the nations, provision of financial and technical support, and a payment system of EEZ fishing access fee. The Japanese salmon industry also has done similar practices, continuing to catch salmon and trout in the Russian EEZ. Additionally, Japan and Russia have attempted to develop joint fisheries projects and to assure fishing operation safety around Kuril Islands. The case of Japan-Russia mutual fishing access shows that a country that has authority over crucial fisheries resources tends to establish specific conditions of mutual fishing access so that it maximizes its national interest. Thus, this case gives us implication what could be future directions of Korea-China-Japan multinational fishing access. The principle of same number of fishing vessels and quantities of catches has worked in existing mutual fishing access to EEZ among Korea, China, and Japan. However, it is expected that a nation that is endowed with abundant fisheries resources would limit counterpart's fishing access to its EEZ. Therefore, Korean fisheries administration should prepare for all possible situations like a dramatic cut in fishing quota and the termination of fishing access. International fisheries cooperation and payment of fishing access could be viable options for such a situation.

SG-RBAC : Role Based Access Control Model for Smart Grid Environment (SG-RBAC : 스마트그리드 환경에 적합한 역할기반접근제어 모델)

  • Lee, Woomyo;Lee, Gunhee;Kim, Sinkyu;Seo, Jungtaek
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.23 no.2
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    • pp.307-318
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    • 2013
  • Smart grid is composed of variable domains including different systems, and different types of the access control are needed in the multiple domain. Therefore, the access control model suitable for the smart grid environment is required to minimize access control error and deny the unauthorized access. This paper introduce the access control requirements in the smart grid environment and propose the access control model, SG-RBAC, satisfied with the requirements. SG-RBAC model imposes constraints on the access right activation according to the user property, the role property, and the system property. It also imposes constraints on the delegation and the inheritance of access right according to temporal/spatial information and a crisis occurrence.

A Proposal for the Acceptance and Processes of Open Access in Korean Societies (국내 학회의 오픈액세스 수용과 추진방식에 대한 제안)

  • Kim, Gyuhwan
    • Journal of the Korean Society for information Management
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    • v.31 no.3
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    • pp.111-131
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    • 2014
  • The purpose of this study was to propose a guide for the acceptance and processes of open access in Korean Societies. Firstly, this study developed journal publishers' open access model focused on the relationship between types and strategies of open access. Secondly, this study investigated current status of journal publishers' open access strategies and the adoption degrees through SHERPA/RoMEO, DOAJ and PMC databases. Finally, on the basis of the result, this study proposed a guide to help Korean societies make journals more open or less open according to their situations as real. Korean societies can make informed decisions about how to derive open access.

A Study on the Directions of Authorized Access Points in KCR4 (한국목록규칙에서 전거형 접근점의 방향성에 관한 연구)

  • Lee, Mihwa;Rho, Jee-Hyun
    • Journal of Korean Library and Information Science Society
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    • v.47 no.1
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    • pp.47-69
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    • 2016
  • This study was to suggest the directions of and the choice of the authorized access points for Korean Cataloging Rules, based on the trends of the international cataloging and the need of rules for the authorized access points in KCR. The Literature review, the case study, and the interviewing were used as the research methods. In the literature review, the Authorized access points were reviewed in FRBR conceptual model, International cataloging Principle 2009, and Resource Description and Access. VIAF authorized access points were analyzed as case study. Last interview was executed with the representative librarians in 4 University libraries. Through these surveys, new directions and rules of the authorized access points for KCR were suggested. This study could contributed to construct work and expression authorized access points of FRBR, and to set up the selection rules of the authorized access points for KCR.

Development of Security Metric of Network Access Control (네트워크 접근제어 시스템의 보안성 메트릭 개발)

  • Lee, Ha-Yong;Yang, Hyo-Sik
    • Journal of Digital Convergence
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    • v.15 no.6
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    • pp.219-227
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    • 2017
  • Network access control should be able to effectively block security threats to the IT infrastructure, such as unauthorized access of unauthorized users and terminals, and illegal access of employees to internal servers. From this perspective, it is necessary to build metrics based on relevant standards to ensure that security is being met. Therefore, it is necessary to organize the method for security evaluation of NAC according to the related standards. Therefore, this study builds a model that combines the security evaluation part of ISO / IEC 15408 (CC: Common Criteria) and ISO 25000 series to develop security metric of network access control system. For this purpose, we analyzed the quality requirements of the network access control system and developed the convergence evaluation metric for security of the two international standards. It can be applied to standardization of evaluation method for network access control system in the future by constructing evaluation model of security quality level of network access control system.

Distributed UORA Scheme for Autonomous Train Communication in Congested Environment (자율주행 열차의 혼잡 상황 통신을 위한 분산형 UORA 기법)

  • Ahn, Woojin;Kim, Ronny Yongho
    • Journal of Advanced Navigation Technology
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    • v.23 no.6
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    • pp.542-547
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    • 2019
  • Autonomous train is investigated to increase the capacity of railroad, and the reliability of wireless communication plays a critical role in terms of decreasing the inter-train distance. In this paper, we propose a transmission scheme for autonomous train communication in highly congested environment. The proposed scheme, namely distributed uplink orthogonal frequency division multiple access (OFDMA) random access (UORA), applies the triggered uplink access (TUA) and the UORA, introduced in the sixth generation WLAN standard, IEEE 802.11ax, for communication devices on vehicle and platform in a distributed manner. The simulation results show that the proposed scheme efficiently improves the packet transmission success rate in highly congested channel conditions compared to the conventional enhanced distributed channel access (EDCA) transmission scheme.

Prioritized Random Access Control for Fairness Improvement in Wireless-Powered Communication Networks (무선전력 통신 네트워크에서 공평성 향상을 위한 우선순위 기반 랜덤 접속 제어)

  • Choi, Hyun-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.22 no.1
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    • pp.175-182
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    • 2018
  • As Internet of things with a large number of nodes emerges, wireless-power communication networks (WPCN) based on a random access protocol needs to be investigated. In the random access-based WPCN, a terminal accessing later in given random access (RA) slots can harvest more energy before transmission and thus can transmit data with higher power and achieve higher throughput if the access is successful. On the basis of this property, the proposed random access control protocol gives the terminals priority and distinguishes the RA slots according to the priority level, so that a near terminal with access point allows to access preferentially other than a remote terminal. This operation decreases the throughput of near terminal and increases the throughput of remote terminal, and then, the doubly near-far problem in WPCN is resolved and the user fairness is improved. Results show that the proposed random access control improves both channel throughput and user fairness according to the priority level.

Performance Analysis of Opportunistic Spectrum Access Protocol for Multi-Channel Cognitive Radio Networks

  • Kim, Kyung Jae;Kwak, Kyung Sup;Choi, Bong Dae
    • Journal of Communications and Networks
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    • v.15 no.1
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    • pp.77-86
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    • 2013
  • Cognitive radio (CR) has emerged as one of effective methods to enhance the utilization of existing radio spectrum. Main principle of CR is that secondary users (SUs) are allowed to use the spectrum unused by primary users (PUs) without interfering PU's transmissions. In this paper, PUs operate on a slot-by-slot basis and SUs try to exploit the slots unused by PUs. We propose OSA protocols in the single channel and we propose an opportunistic spectrum access (OSA) protocols in the multi-channel cognitive radio networks with one control channel and several licensed channels where a slot is divided into contention phase and transmission phase. A slot is divided into reporting phase, contention phase and transmission phase. The reporting phase plays a role of finding idle channels unused by PUs and the contention phase plays a role of selecting a SU who will send packets in the data transmission phase. One SU is selected by carrier sense multiple access / collision avoidance (CSMA/CA) with request to send / clear to send (RTS/CTS) mechanism on control channel and the SU is allowed to occupy all remaining part of all idle channels during the current slot. For mathematical analysis, first we deal with the single-channel case and we model the proposed OSA media access control (MAC) protocol by three-dimensional discrete time Markov chain (DTMC) whose one-step transition probability matrix has a special structure so as to apply the censored Markov chain method to obtain the steady state distribution.We obtain the throughput and the distribution of access delay. Next we deal with the multi-channel case and obtain the throughput and the distribution of access delay by using results of single-channel case. In numerical results, our mathematical analysis is verified by simulations and we give numerical results on throughput and access delay of the proposed MAC protocol. Finally, we find the maximum allowable number of SUs satisfying the requirements on throughput and access delay.

A Study on the CLR Performance Improvement for VBR Traffic in the Wireless ATM Access Network (무선 ATM 가입자망에서 VBR 트래픽의 CLR 성능개선)

  • 이하철
    • Journal of Korea Multimedia Society
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    • v.7 no.5
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    • pp.713-720
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    • 2004
  • In this paper we suggest error control scheme to improve CLR performance degradation on wireless ATM access networks which consist of access node and wireless channel. Based on the cell scale and hurst scale, traffic model of wireless ATM access network is analyzed. The CLR equation due to buffer overflow for wireless access node is derived for VBR traffic. the CLR equation due to random bit errors and burst errors for wireless channel is derived. Using the CLR equation for both access node and wireless channel, the CLR equation of wireless ATM access network is derived, and we evaluate the CLR performance on the wireless ATM access networks with conventional SR ARQ scheme and recommended error control scheme, that is, Type I Hybrid ARQ scheme. It is confirmed that CLR performance of the access networks with recommended error control schemes is superior to that of access networks with conventional error control scheme.

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Current treatment status and medical costs for hemodialysis vascular access based on analysis of the Korean Health Insurance Database

  • Lee, Hyung Seok;Ju, Young-Su;Song, Young Rim;Kim, Jwa Kyung;Choi, Sun Ryoung;Joo, Narae;Kim, Hyung Jik;Park, Pyoungju;Kim, Sung Gyun
    • The Korean journal of internal medicine
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    • v.33 no.6
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    • pp.1160-1168
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    • 2018
  • Background/Aims: The Republic of Korea is a country where the hemodialysis population is growing rapidly. It is believed that the numbers of treatments related to vascular access-related complications are also increasing. This study investigated the current status of treatment and medical expenses for vascular access in Korean patients on hemodialysis. Methods: This was a descriptive observational study. We inspected the insurance claims of patients with chronic kidney disease who underwent hemodialysis between January 2008 and December 2016. We calculated descriptive statistics of the frequencies and medical expenses of procedures for vascular access. Results: The national medical expenses for access-related treatment were 7.12 billion KRW (equivalent to 6.36 million USD) in 2008, and these expenses increased to 42.12 billion KRW (equivalent to 37.67 million USD) in 2016. The population of hemodialysis patients, the annual frequency of access-related procedures, and the total medical cost for access-related procedures increased by 1.6-, 2.6-, and 5.9-fold, respectively, over the past 9 years. The frequency and costs of access care increased as the number of patients on hemodialysis increased. The increase in vascular access-related costs has largely been driven by increased numbers of percutaneous angioplasty. Conclusions: The increasing proportion of medical costs for percutaneous angioplasty represents a challenge in the management of end-stage renal disease in Korea. It is essential to identify the clinical and physiological aspects as well as anatomical abnormalities before planning angioplasty. A timely surgical correction could be a viable option to control the rapid growth of access-related medical expenses.